Apparatus for making printing rolls



May 2, 1933- Ajc. GIRDwoYN 1,906,572

/ APPARATUS FOR MAKING PRINTING ROLLS Filed April 20, 1931 INVEN'TOR ZWMC @dam/fn. v

' ATTORNEYS llblllllllllllxhlllll MIIIVI l IIIIIIIWI Patented May `2,1933y UNITED lSTATES PATENroFFicE ALBERT C. erIRmvoYN,A oF SOMERSET,MASSACHUSETTS, AssrGNoR To Aia/LER'ICANv PRINTING COMPANY, or ram,yRIVER, MASSACHUSETTS, A CoRroRATIoN QEMAS-y Y SACHUSETTS ArrARATUS FCRMAKING PRiNTNG ROLLS Application filed April 20, 1931. Serial No.531,35?.

This invention relates to the art of producing rolls for the continuousprinting of fabrics, paper, and 'the like, and is concerned moreparticularly with'a machine for transferring a design to the surface ofa printing rollpreliminary to the etching of the roll.

In the production of printing rolls, a pro- Y cedure'frequently followedinvolves the steps of preparing a flat zinc plate carrying repetitionsof the design, and transferring the design from the plate to the surfaceof a blanket, and then from the` blanket to the surface of the roll. Thezinc plate is produced by photographic methods, and according to one rmethod, anegative is made of the complete design and this negative isphotographed on the sensitized surface'of the zinc plate the desirednumber of times in photographic apparatus, such as a step-and-repeatmachine. In making the negative, the design is reduced or enlarged'tothe end that the total area lof `the reproductions on the yzinc platemay correspond as closely as possible to thev surface area oftheprinting roll, but even with the best methods, it is frequently foundthat the ends of the pattern do not match exactly on the roll. Thatmakes the roll useless for of the pattern on the roll results in defectsin the material being printed.

Machines of various types vised for transferring the design from thezinc plate to the roll and in those machines provision has been madeforeecting an exact printing purposes, `since any gap or overlap ymatching of the ends of the pattern on the roll by causing the roll toslip relative to the blanket during the transfer operation. In onemachine, it has been proposed, for eX- ainple, to transfer tie design tothe roll by placing the roll in contact with the blanket and rotatingthe roll by its friction al Contact with the blanket which is positivelydriven; in addition to the friction drive for the roll, a positive drivefor the roll is provided for the purpose of retardiiig or acceleratingthe roll to the extent necessary to produce the slippage required. TheeXpedients suggested, while providing for a delicate adjustment aresomewhat complicated in construction.

It is accordingly the object of this invenhave been den t the machine inside elevation with the parts tion to provide a transfer machine of thetype above generally Vdescribed in which the exact matching of the endslof the pattern transferred to the copper roll is effect-ed by a simplevand inexpensive mechanism which is easy to operate and does not get outof order. In the machine, I V provide a support for the Zinc plate, acylinder with its blanket mounted in a carriage which is movable overthe support, ,i

and bearings on the carriage for the journals yof the copper roll.

operative 'means effective to accelerate or re-' vtard the copper rollduring the time that itis I also provide gravity rotating in Contactwiththe blanket.j One convenient forni ofthe vaccelerating andretardiiig means may be straps and weights which may be Aconnected tothe shaft of the copper roll so as toassist or oppose rotation of thatroll produced by its contact with the blanket. `In addition to thestrapsr and weights, the machine maybe provided `with a suitable brakemechanism which may be used 'in substitution for or in combiii ationwith the straps and weights for retarding purposes, Y

the brake mechanism being preferable tothe straps andfweights because ofgreaterease of `control of the retardiiig action.

Fora better understanding of theinvention, reference may be had to theaccompanying drawing in which y Y Fig. 1 is a'view of the main featuresof in the positions which they assume inthe operation of transferringthe design from the plateV to the blanket;

Figs. 2 and 3 are views in vertical longitudinal section of thefeaturesillustrated in Fig. 1, showing the retarding and acceleratingmechanism,respectively, and

Fig. 4 1s a plan view of the mechanism illustrated in Fig. l. l

Referring now to the drawing, the machine is Yillustrated as including apair of longitudinal members l() which may be supported on any suitablelegs or base. Between these members and near one end thereof is ay bedplate 1l on ywhich may be disposed the latzinc plate carrying thereproductions of the design, A carriage 12 comprising side members and atop piece is mounted on the longitudinal members 10 and is movablelengthwise of the machine on rollers 13 running in guideways 14 formed,for example, in the sides of the members 10. Racks 15 are provided alongthe tops of the members 10, these racks extending substantiallythroughout the length of the members 10 and having relatively deepteeth. A shaft 16 operable by a handle 17 extends across the carriageand carries pinions 18 meshing with the racks, so that rotation of theshaft 16 causes the carriage to move along the members 10.

Mounted in the carriage is a shaft 19 for the blanket cylinder 2U, thiscylinder carrying a rubber blanket 21, the ends of which enter anopening in th-e cylinder and are secured by clamping devices 22 by whichthe blanket can be held taut. The shaft 19 is supported eccentrically inbearings 23 mounted in supports 2&1, the supports being rotatable bymeans of a handle 25 on a shaft 25V mounted on the carriage andconnected by linkage 26 to crank arms 27 projecting from the supports.By operation of the shaft 25a, the shaft 19 may be raised and lowered tobring the blanket surface into and out of contact with the zinc plate.Gears 19a on shaft 19 mesh with the racks 15 to cause cylinder 20 torotate when the carriage is moved along, and the construction of theteeth of the gears is such that the cylinder may be raised slightlyabove the plane of the Zinc plate on support 11 and still be rotated bythe gears and racks as the carriage moves. Also, the shaft 19 may have asquared end to which a handle may be applied in the usual way forrotation of the cylinder without moving the carriage. Y

The carriage is provided at one end with extensions 28 on which aremounted sliding blocks 29 carrying bearings 3() for the shaft 31 of acopper roll 32, the blocks being engaged by screws 33 having cranks 34which may be operated to move the blocks and roll toward' and away fromthe blanket cylinder. In each block 29 above the shaft 31 is a brake`shoe 35 operated upon by a screw 36, the

screw being mounted in a. plate 37 hinged to the top of the block 29 andcovering'the opening formed in the block for the reception of bearing30, shaft 31, and brake shoe 35. This hinged construction permits theplate 37 to be swung away from the block 29 so that the brake shoe 35may be removed and the roll lifted free and another one inserted inposition.

In the operation of the parts so far described, the Zinc plate is placedon the bed plate 11 and prepared for the transfer operation in the usualway. The carriage is then moved to a point near the end of the plate,and the blanket cylinder lowered into con tact with the plate. Thecarriage is .then moved over the plate and in this operation.

the blanket cylinder rolls over the plate and the design is transferredfrom the plate to the blanket. During these operations, the copper rollis backed away from the blanket surface as illustrated in F ig. 1. Thecarriage is now moved away from the zinc plate, the blanket cylindermoved to its raised posi tion if desired, and the copper roll forcedinto contact with the blanket surface at the desired pressure. Theblanket cylinder may now be rotated by appropriate means such as thehandle, if the cylinder is in fully raised position, or if the cylinderis only partially raised and in a posit-ion in which gears 19a stillremain in mesh with the racks, the rotation of the cylinder may beaccomplished by movement of the carriage along the support. In eithercase, the blanket cylinder is rotated so as to transfer the design tothe roll during a single rotation of the latter.

lf the design picked up by the blanket has exactly the same length asthe circumference of the roll, the pattern will be applied to the rollwith its ends exactly meeting. flowever, it is usually found that thereis a slight dilferencein the length of the design on the blanketand thecircumference of the roll, and this difference can be corrected toproduce an exact matching of the ends of the pattern on the roll bycausing the roll to slip slightly with reference to the blanket and thushave either a greater or less periph eral speed than the blanket.

In my machine, the slippage of the roll relative to the blanket may beaccomplished by securing to the shaft 31 of the roll at each end a strap33 which carries at its lor/er end one or more weights 39. These strapsmay hang down from the shaft on either side of the axis thereof. Viliththe parts in the position illustrated inllig. 2, the blanket cylinder2() will be rotated in a counter-clockwise direction to effect thetransfer of the copper roll, and the roll itself will move clockwiseduring the transfer ope ation With the strap applied to the shaft of theroll as illustrated, the weights are raised the roll rotates and theweights thus oppose the rotae tion of the roll and cause retardation andslippage. The amount of this slippage is determined by the number andsize of the weights on the end of the straps and, by proper selection ofthe weights, it is possible to effect the slippage required to producethe exact matching of the pattern ends on the roll. When the design onthe blanket is slightly longer than the circumference of the roll, thestraps and weights are used in the manner illustrated in lfig. 2 andsince the slippage of the roll with reference to the blanket isdistributed tliroughout the length of the pattern, no distortion isvisible where the difference in length of the pattern and thecircumference of the roll is relatively small.

In the construction illustrated in Fig,V 3, the straps and Weights havebeen applied to accelerate the roll when the latter is rotated in aclockwise direction andthis arrangement of the straps and weights isemployed where the length of the design is slightly less than thecircumference of theroll.

When the straps and Weights are employed in the manner above describedfor accelerat-` ing or retarding the roll, the brake shoes rest lightlyon vthe shaft of the roll andr are without efi'ect. fords a means forret-arding the copper roll which is somewhat more convenient to operatethan the straps and weights. In general,

better results are obtained when the correction is madelby retarding thecopper roll relative to the blanket and the desiredretardation may beobtained vby usingk either the straps and weights in the mannerillustrated in'Fig. 2 or the-brake mechanism shown inV Fig., l or bothin combination.

When the brakes are employed, the braking j effective for the purposefor which it isintended. Since the brakes offer a more .convenient andsatisfactory means` for producing the slip and serve only to retardtheroll and thus correct for an excess ofthe design, I prefer that thezinc plates carry a design which is slightly longer than thecircumference of the roll'. This slight excess can be easily obtainedduring the photographic process incident to the preparation of theplate.

VVhatl claim is l. A machine for producing printing rolls, whichcomprises a support for a flat member carrying` a design, a curvedmember carrying a blanket, a cariiage movable over the ilat member,means on .the'carriage for supporting the curved member and operable tomove said member into contact with the flat member, supports on thecarriage for the journals of a printing roll, said ysupports beingadjustable toward and away from the curved member to move the printingroll into and out of contact with the curved member, means for rotatingthe curved member and printing roll while they are in contact, andgravity operative means for varying the peripheral velocity of theprinting roll relative to that of the curved member While the tWo are incontact.

This brake ,mechanism af- 2. A machine for producing printingrolls,which comprises a `support for a flat member carrying a design, a curvedmember carrying va blanket, a carriage.movablef -overth'e flatmember,means on the carriage for supporting the curved member andoperable to move said member into contact with the flatfmember, supportson the carriage for the journals of a printing roll, saidksupports'beingadjustable toward and away fromithe curved i member tomove theprinting roll into/and out of contact With the curved member,means i for rotating the curved member and printing rollv whilethey arein contact, and gravityactuated means and brake means operable on a partrotating with the printing roll for accelerating and retarding it withreference to b the curved member when the two are rotating incontact,.said means being employed asalternatives. f

3., A machine for producingprinting rolls, n

which comprises a support for aftlat member carrying a design, a curvedmember carrying a blanket, a carriage rmovable over the flat member,means on the carriage for supporting the curved member and operable tomove said member into contact with the flat member, supports onthecarriage for the journals'of a printing roll, saidA supports beingadjustable toward and away from the curved attachable toa part rotatingwith the printingroll and effective to vary the peripheral velocityofthe roll relative to that of the curved member, lwhile the two are incontact.V

4. Amachine for producing printing rolls, `which comprises asupport fora'flat Amemberl carrying a design. wa curved member carrying a blanket,a carriage movable over the Hat member, means on the carriage forsupporting the curved member Aand operable to'move said member intocontact with the flat member, supports onthe carriage for the journalsof a printing roll, said supports being adjustable toward and away fromthe curved member to move the printing roll into and out of contact withthe curved member, means for yrotating the curved member and 4 member tomove the printing roll into and Vout of Contact with the curved member,means for rotating the curved member and printingv roll while they arein contact, and a Weight printing roll While they are in contact, a'strap attachable to a part rotating with the printing roll, and aWeight secured to thestrap, said strap and weight being operable in twopositions of dependence from said journal alternately to accelerate orretard said printingroll relative to said curved member When the tworotate in contact.

5. A machine for producing printing rolls,

which comprises a support for a 'flat member carrying a design, a curvedmembe'rcarrying a blanket,`a carriage movable over the flat member,means onthe carriage for supporting the curved member and operable'tomove said member into contact with the flat member, supports on thecarriage for the journals of a printing roll, said supports beingadjustable toward and awayfrom the curved member to move the printingroll into and out of contact withthe curved member, means for rotatingthe curved member and printing roll while they are in Contact, and abrake operable on a part rotating with said printing roll and effectiveto retard the printing roll relative to the curved member while the tworotate in Contact.

6. A machine for producing printing rolls, which comprises a support fora flat member carrying a design, a curved member carrying a blanket, acarriage movable over the llat member, means on the carriage forsupporting the curved member and operable to move said member intoContact with the flat member, supports on the carriage for the journalsof a printing roll, said supports being adjustable toward and away fromvthe curved member to move the printing roll into and out of contact withthe curved member,

' means for rotating the curved member and printing roll while they arein contact, a weight attachable to a part rotatable with the printingroll and operable to accelerate said roll relative to said curved memberwhile the two rotate in contact, and a brake operable on a partrotatable with said printing roll to retard said roll relative to saidcurved member, said brake and weight being employed as alternatives.

7. In a machine for producing printing rolls, the combination of ablanket mounted to provide a curved surface, a printing roll movableinto engagement with said blanket, means for rotating the blanket androllin contact, and gravity operative means for Varying the relativeperipheral velocities of the blanket and printing roll while they rotate in contact.

8. In a machine for producing printing rolls, the combination of ablanket mounted to provide a curved surface, a printing roll movableinto engagement with said blanket, means for rotating the blanket androll in contact, and a strap carrying` a weight and attachable to a partrotating with the printing roll, said strap having two positions ofattachment and being operable in one position to increase, and in theother to decrease, the peripheral velocity of the printing roll relativeto that of the blanket while the two rotate in Contact.

9. In a machine for producing printing rolls, the combination oi`l ablanket mounted to provide a curved surface, a printing roll movableinto engagement with said blanket, means for rotating the blanket androll in Contact, a strap carrying a weight and attaclir able to a partof the printing roll, said strap and weight being effective to increasethe peripheral velocity of the printing rollrela-

